The present invention relates generally to a collision-avoidance system for a vehicle, and more particularly to an active collision-avoidance system employing an automatic brake system for a vehicle.
Recent years, there have been disclosed various automatic brake systems for collision-avoidance. One such system is disclosed in Japanese Patent Provisional Publication No. 6-298022 published Oct. 25, 1994. In the system of this publication, a first minimum safety distance in which a collision can be avoided by a brake pedal operation and a second minimum safety distance in which a collision can be avoided by a steering wheel operation are both calculated for an obstacle preceding the host vehicle. When a detected distance between the host vehicle and the obstacle is smaller than both the first and second minimum safety distances, an automatic braking control is operated. In other words, possibilities of collision-avoidance by steering and by braking are determined based on the first and second distances. When the collision-avoidances by steering and by braking are both impossible, an automatic braking control is operated to prevent a collision. In this way, an unnecessary automatic braking is avoided when a driver intends to avoid a collision with a obstacle by braking or by steering.